Platen-type belt grinder

ABSTRACT

The frame of the grinder includes inner and outer spaced apart sidewalls. The abrasive belt idler roll is carried by a cylinder and piston structure which is fixed to one of the sidewalls. The platen-supporting member is fixed to the other sidewall, whereby stresses developed in the cylinder are not transmitted to the platen.

United States Patent Robert L. Schaller Camillus, N.Y.

July 23, 1969 May 25, 1971 Sundstrand-Engelberg Inc. Syracuse, NY.

lnventor App]. No. Filed Patented Assignee PLATEN-TYPE BELT GRINDER 5 Claims, 6 Drawing Figs.

US. Cl 51/148 Int. Cl B24b 21/00,

B24b 23/06, B24b 25/00 FieldofSearch ..51/l48,137

[56] References Cited UNITED STATES PATENTS 3,422,576 1/1969 Hobble 51/148 3,5l0,988 5/1970 Mason 51/148 3,176,436 4/1965 Anton 5l/148X Primary Examiner-James L. Jones, Jr. AttorneyD. Emmett Thompson ABSTRACT: The frame of the grinder includes inner and outer spaced apart sidewalls. The abrasive belt idler roll is carried by a cylinder and piston structure which is fixed to one of the sidewalls. The platen-supporting member is fixed to the other sidewall, whereby stresses developed in the cylinder are not transmitted to the platen.

PATENTEU HAY25 197i SHEET 1 BF 3 INVENTOR; ROBERT L. SCHALLER.

ATTORNEY.

PATENTEU "M25 197i SHEET 2 [IF 3 vFIG. 2

I lull INVENTOR. ROBERT L. SCHALLER.

ATTORNEY.

PATENTEU HAYZS 1971 SHEET 3 OF 3 FIG. 4

INVENTOR. ROBERT L. SCHALLER.

ATTORNEY.

PLATEN-TYIPE BELT GER BACKGROUND OF THE INVENTION In platen-type belt grinding machines wherein the platen is disposed in vertical position, difficulty is incurred in maintaining the platen in precise position. Such stresses are developed during operation of the machine by the abrading belt and are imparted to the idler roll, which is yieldingly mounted to maintain proper tension on the belt. Such stresses are transmitted from the idler roll to the frame structure of the machine and thence to the platen to provide for the absorption of such stresses before they reach the platen. Such grinding machines have been constructed with an exceptionally heavy and rigid framework, which adds materially to the cost of producing the machine.

This invention has as an object a platen-type belt grinder, the frame structure of which includes vertically disposed inner and outer sidewall plates extending in parallel spaced relation. The idler roll support, which is usually a fluid-operated cylinder, is fixedly secured to one sidewall plate, and the platen-supporting member is fixedly secured to the other sidewall plate. The supporting means for the idler roll and the platen being isolated one from the other, whereby stresses developed in the idler roll support are not transmitted to the platen, with the result that it remains in precise position.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a front elevational view, with parts broken away and parts in section, of a belt grinding machine embodying my invention.

FIG. 2 is a side elevational view, looking to the right, FIG. 1.

FIG. 3 is a transverse sectional view taken on line 3-3, FIG. 2.

FIG. 4 is a view, in perspective, of the platen-supporting member.

FIG. 5 is a view similar, but in reverse from that shown in FIG. 4.

FIG. 6 is a view taken on line 6-6, FIG. 1.

DETAILED DESCRIPTION The frame structure of the machine includes a base 10, to which there is fixedly secured, as by welding, inner and outer vertically disposed sideplates 11, 12. An arbor housing 13 is fixed in the lower portions of the sidewall plates 11, 12, as by welding. An arbor 14 is joumaled in the housing 13, with an end portion 16 of the arbor extending laterally from the inner sidewall plate 11. The opposite end portion 17 of the arbor extends laterally from the outer sidewall 12 and is provided with a belt pulley 18 to receive a driving belt 20 powered by a motor, not shown, mounted on the baseplate 10. An abrasive belt driving roll 23 is mounted on the end portion 16 of the arbor 14.

An idler roll 25 is joumaled on a shaft 26, one end of which is pivotally connected at 27 to a leg 28 of a yoke 29. The leg 30 of the yoke is formed with a vertically disposed slot to receive the opposite end of the shaft 26 which is adjusted about pivot 27 by screw 31 for tracking the abrasive belt 33 which is trained about the rolls 23, 25.

The yoke member 29 is fixedly secured to the upper end of a piston rod 34 mounted in a cylinder 35. The cylinder 35 is fixedly secured to the outer sidewall I2. In the arrangement shown, a pair of arms 36, 37, are welded to the inner surface of the wall 12 and extend inwardly. The arm 36 extends through an aperture 38 formed in the inner sidewall plate 11. The arm 37 extends through an aperture 39 formed in the inner plate. The apertures 38, 39, are dimensioned to provide clearance about the arms 36, 37, so that they have no connection to the inner sidewall 11. The inner ends of the arms 36, 37, have affixed thereto pads 40, 41, which are formed with threaded apertures 42 to receive bolts by which the cylinder 35 is fixedly secured to the arms. Stay plates 43, see FIGS. 1 and 3, are welded to the inner surface of the outer sidewall plate 12. They are also welded at their lower ends to a crossmember 44, and at their upper ends to a crossmember 45. The stay plates 43 are also welded to the arms 36, 37. This arrangement provides a rigid column structure for supporting the cylinder 35.

A platen support of boxlike structure, indicated generally at 51, see FIGS. 4 and 5, is fixedly mounted on the inner sidewall 11. A pair of bars 53 are welded to the inner sidewall 11. The sidewall 55, of the platen support 51, is formed with apertured pads 56, see FIG. 5, and the bars 53 are formed with threaded apertures to receive screws 57, extending through the apertured bosses 56, and serving to fixedly secure the platen support to the bars 53.

The platen support member is formed with a sidewall 60 opposite the sidewall 55, a rear wall 61, and a front wall 63. Transversely extending bars 65, 66, are attached to the lower and upper portions of the front wall 63. The lower bar 65 is formed with a V-shaped rib to receive a corresponding groove in the bottom edge of the platen 67. The upper bar is formed with a threaded aperture to receive a clamping screw extending into the V groove 71 formed in the upper edge of the platen 67. With this arrangement, the platen is mounted on the support and is positioned immediately behind the forward down run of the belt 33.

The platen support is formed with a closed bottom wall 75 and a top wall 77. The cylinder 35 is positioned within the platen support member 51 and extends upwardly through a large opening formed in the top wall 77, as shown in FIGS. 1 and 2. Reinforcing ribs extend inwardly from the sidewalls 55, 60, rear wall 61 and the front wall 63. The ribs 80 in the top wall 77 are dimensioned to provide clearance for the cylinder 35, whereby it has no connection with the platen support 51. The sidewall 55 is formed with an opening 83 to receive the lower cylinder supporting arm 37. The upper arm 36 is positioned above the platen support, see FIGS. 1 and 3. The upper portion of the sidewall 60 is cut away, as at 85, to permit access to the screws 57, and the wall is also formed with an opening 87 to permit access to the cylinder attaching screw threading into the aperture 42 of the lower arm 37.

Shims may be positioned between the bars 53 and the pads 56 on the platen support 51 to locate the outer face of the front wall 63 of the support, and accordingly the platen 67, in precise parallel relationship to the axis of the arbor 14. When capscrews 57 are tightened, screws 90, threaded in lugs 91 welded to the inner ends of the bars 53, are tightened against the rear wall 61 of the platen support. As is well known, the major force against the platen results from pressure of the workpiece against the front down run of the belt 33. The backup screws 90 assist the capscrews 57 in maintaining the platen support in proper aligned position.

In the structural arrangement described, it will be apparent that the-cylinder 35, supporting the upper idler roll 25, is fixedly mounted on the outer sidewall 43 and has no connection with the platen support 51. The support 51 is fixedly attached to the inner sidewall plate 11. Accordingly, any stresses developed in the outer sidewall plate 12 are not transferred to the inner sidewall plate 11 and thence to the platen 67. This permits the platen to be initially adjusted with precision, and the platen is not moved out of adjusting position by strains transmitted to the idler roll during operation of the machine.

Iclaim:

1. A platen-type belt grinding machine comprising a frame structure including a base, inner and outer sidewall plates fixed to said base and extending in parallel spaced apart relation, an arbor housing fixed in like end portions of said sidewall plates, an arbor joumaled in said housing and having end portions extending laterally from said plates, an abrasive belt driving roll fixed to the end portion of said arbor extending from said inner side plate, a power-driven pulley fixed to the opposite end portion of said arbor, cylinder-supporting means fixedly mounted on one of said sidewall plates and being disconnected to said other sidewall plate, a cylinder carried by'said supporting means and extending normal to the axis of said belt driving coil, said cylinder having a piston rod extending in a direction away from said driving roll, a yoke member mounted on said piston rod, an idler roll journaled in said yoke, an abrasive belt trained about said rolls, said cylinder and piston being operable to urge said idler roll in a direction away from said driving roll to maintain tension on said abrasive belt, a platen-supporting member fixedly mounted to said other sidewall plate and having a surface extending in parallel relation to one run of said abrasive belt, and a platen detachably mounted on said surface.

2. A grinding machine as set forth in claim 1, wherein said cylinder-supporting means is affixed to said outer sidewall plate, and said platen-supporting member is affixed to said inner sidewall plate.

3 A grinding machine as set forth in claim 1, wherein said inner sidewall plate is formed with an aperture and said cylinder-supporting means consists of an ami fixed to said outer sidewall plate and extending through said aperture, said aperture being formed with clearance about said arm.

4. A grinding machine as set forth in claim 1, wherein said platen-supporting member consists of a boxlike formation enclosing said cylinder.

5. A grinding machine as set forth in claim 1, wherein said cylinder-supporting means includes a pair of arms fixed to the inner surface of said outer sidewall and extending through said inner sidewall in disconnected relation thereto, a pair of stay plates extending in a direction parallel to said cylinder, said stay plates being welded to said outer sidewall plates and to said arms. 

1. A platen-type belt grinding machine comprising a frame structure including a base, inner and outer sidewall plates fixed to said base and extending in parallel spaced apart relation, an arbor housing fixed in like end portions of said sidewall plates, an arbor journaled in said housing and having end portions extending laterally from said plates, an abrasive belt driving roll fixed to the end portion of said arbor extending from said inner side plate, a power-driven pulley fixed to the opposite end portion of said arbor, cylinder-supporting means fixedly mounted on one of said sidewall plates and being disconnected to said other sidewall plate, a cylinder carried by said supporting means and extending normal to the axis of said belt driving coil, said cylinder having a piston rod extending in a direction away from said driving roll, a yoke member mounted on said piston rod, an idler roll journaled in said yoke, an abrasive belt trained about said rolls, said cylinder and piston being operable to urge said idler roll in a direction away from said driving roll to maintain tension on said abrasive belt, a platen-supporting member fixedly mounted to said other sidewall plate and having a surface extending in parallel relation to one run of said abrasive belt, and a platen detachably mounted on said surface.
 2. A grinding machine as set forth in claim 1, wherein said cylinder-supporting means is affixed to said outer sidewall plate, and said platen-supporting member is affixed to said inner sidewall plate.
 3. A grinding machine as set forth in claim 1, wherein said inner sidewall plate is formed with an aperture and said cylinder-supporting means consists of an arm fixed to said outer sidewall plate and extending through said aperture, said aperture being formed with clearance about said arm.
 4. A grinding machine as set forth in claim 1, wherein said platen-supporting member consists of a boxlike formation enclosing said cylinder.
 5. A grinding machine as set forth in claim 1, wherein said cylinder-supporting means includes a pair of arms fixed to the inner surface of said outer sidewall and extending through said inner sidewall in disconnected relation thereto, a pair of stay plates extending in a direction parallel to said cylinder, said stay plates being welded to said outer sidewall plates and to said arms. 